windows-xp/Source/XPSP1/NT/published/ddk/inc/pfhook.h

/*++

Copyright (c) 1999  Microsoft Corporation

Module Name:

    pfhook.h

Abstract:

    Header file for Packet Filter driver extension hook.

--*/

#ifndef _PF_EXTEND_DEFS_H_
#define _PF_EXTEND_DEFS_H_

#define  INVALID_PF_IF_INDEX  0xffffffff
#define  ZERO_PF_IP_ADDR      0

//
// Enumeration constants for values that may be returned by an extension
// routine.
//

typedef enum _PF_FORWARD_ACTION
{
    PF_FORWARD       = 0,
    PF_DROP          = 1,
    PF_PASS          = 2,
    PF_ICMP_ON_DROP  = 3
} PF_FORWARD_ACTION;

//
// Definiton for a filter routine callout.
//

typedef PF_FORWARD_ACTION (*PacketFilterExtensionPtr)(
                              unsigned char   *PacketHeader,
                              unsigned char   *Packet,
                              unsigned int    PacketLength,
                              unsigned int    RecvInterfaceIndex,
                              unsigned int    SendInterfaceIndex,
                              IPAddr          RecvLinkNextHop,
                              IPAddr          SendLinkNextHop
                              );


//
// Structure to be passed to the IOCTL_PF_SET_EXTENSION_POINTER call
//

typedef struct _PF_SET_EXTENSION_HOOK_INFO 
{
    PacketFilterExtensionPtr       ExtensionPointer; 
} PF_SET_EXTENSION_HOOK_INFO, *PPF_SET_EXTENSION_HOOK_INFO;


#define DD_IPFLTRDRVR_DEVICE_NAME   L"\\Device\\IPFILTERDRIVER"

#define FSCTL_IPFLTRDRVR_BASE     FILE_DEVICE_NETWORK

#define _IPFLTRDRVR_CTL_CODE(function, method, access) \
                 CTL_CODE(FSCTL_IPFLTRDRVR_BASE, function, method, access)

#define IOCTL_PF_SET_EXTENSION_POINTER \
            _IPFLTRDRVR_CTL_CODE(22, METHOD_BUFFERED, FILE_WRITE_ACCESS)

#endif // _PF_EXTEND_DEFS_H_